Air pollution levels have been continuously trending lower as Malta’s partial lockdown effort to curb the spread of COVID-19 extended into April and May.
The concentration of nitrogen dioxide (NO2) decreased by an average of 35 per cent across monitoring stations. Data was gathered from the Msida, Żejtun, Attard and Għarb stations between February 19 and April 19.
The Msida station, which typically picks up some of the island’s heaviest traffic, saw a decrease of 25 μg/m3 (micrograms per meter cubed) at its peak hour, a 40 per cent reduction in pollution on average.
In Żejtun, there was a 56 per cent average reduction in NO2 level, with its peak going from just over 35 μg/m3 to just over 15 μg/m3 during the lockdown period.
Attard’s station registered a decrease of 11 per cent, with the peak of NO2 concentration moving from around 7.30 am to earlier in the morning at around 6am.
Readings from the monitoring station in Għarb were negligible, as the station is in a rural area that seldom experiences traffic flow and the source of the pollutants it registers is largely imported and not recorded at source.
Mark Scerri, a lecturer at the Institute of Earth Systems at the University of Malta, said that while registering numerical decreases was important, it was becoming increasingly clear that Malta needed to work on reducing road traffic if it wanted to take a serious approach to reducing air pollution long term.
“Research has shown us that, despite varying due to seasonality and atmospheric conditions, Malta’s primary source of pollution is road traffic and it is time to start looking towards some radical solutions to get results,” Scerri said.
Widening roads to reduce pollution is like realising you’ve gained too much weight and instead of tackling the real problem, you buy yourself a bigger pair of trousers
“Let’s set better targets at teleworking. If a job can be done from home, then why not do so twice a week? If commutes and school runs are clashing and resulting in a peak, we should perhaps consider changing school opening hours.”
Asked if he thought there could be other major contributors to pollution levels in Malta, such as cruise liners, Scerri said he considered the issue a little ‘overblown’.
“Cruise liners mostly affect port areas and the traffic is concentrated between 5am to 10am. You also have the discharge coming from a chimney which is many meters above the ground and so it is dispersed,” Scerri said.
“Cars pollute at ground level, and at much higher frequency and durations.”
From his own research into the Msida harbour area, Dr Scerri found that shipping activity in the area contributed much less pollutant particles than the flow of road traffic.
Despite the overall improvement in air quality, Scerri says the situation might be short lived, as the relaxation of some measures had already seen a visible increase in cars on the road.
“We can only expect pollution levels to start going up from here.”
Asked whether solutions to tackle traffic issues such as road widening would have an impact in seeing a long-term reduction in air pollution, Scerri replied that the effective way to see a reduction would be to tackle it at source.
“Research has indicated that measures like road widening are short lived and effective for a short period of time. Once people realise a particular route is more expedient than the other, they will flock to it and the situation will quickly remain at par,” Scerri says.
“You would also have to curb the increase of cars on the road if you want to impact the density of pollutants emitted.
“Widening roads to reduce pollution to me is like realising you’ve gained too much weight to wear a pair of trousers and instead of tackling the real problem, you buy yourself a bigger pair of trousers.”